IPM - Brain Engineering Center


Weekly Seminars - JUN 1, 2016

An optogenetic approach to understanding temporal lobe epilepsy
Wednesday, JUN 1, 2016 (15:00 - 17:00)
Zahra Shiri Varnaamkhaasti
McGill University, Montreal

Seizures occurring in temporal lobe epilepsy patients and in experimental models mimicking this neurological disorder can be classified, based on their onset pattern, into low-voltage, fast versus hypersynchronous onset seizures. It has been suggested that the low-voltage, fast onset pattern is mainly contributed by interneuronal (gabaergic) signaling, whereas the hypersynchronous onset involves the activation of principal (glutamatergic) cells. Here, we tested this hypothesis using the optogenetic control of two types of interneurons and of principal cells in the mouse entorhinal cortex in the in vitro 4-aminopyridine model of epileptiform synchronization. We found that during 4-aminopyridine application, both spontaneous seizure-like events and those induced by optogenetic activation of interneurons displayed low-voltage, fast onset patterns. In contrast, seizures induced by the optogenetic activation of principal cells had a hypersynchronous onset pattern. Our results firmly establish that under a similar experimental condition (ie, bath application of 4-aminopyridine), the initiation of low-voltage, fast and of hypersynchronous onset seizures in the entorhinal cortex depends on the preponderant involvement of interneuronal and principal cell networks, respectively.

The seminar will be held at the conference room of Particles and Accelerators school, IPM, Larak, Tehran


webmaster | ipmic@ipm.ir   Copyright © 2016, All rights reserved.